jlarkin@highlandsniptechnology.com wrote:
> leads to this one...
> 
> https://www.dropbox.com/s/cgaxalnn3hhf315/RRIO_Logamp.jpg?raw=1
> 
> where we use the substrate diode of a RRIO opamp as a logarithmic
> current-to-voltage converter.
> 
> There are better ways to do this, but maybe none so cute.
> 
> 
> 
> 

Assuming your op amp's common mode range goes that far.  Which one is it?

Cheers

Phil Hobbs

-- 
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

On Friday, October 15, 2021 at 2:52:10 PM UTC+11, jla...@highlandsniptechnology.com wrote:
> leads to this one... 
> 
> https://www.dropbox.com/s/cgaxalnn3hhf315/RRIO_Logamp.jpg?raw=1 
> 
> where we use the substrate diode of a RRIO opamp as a logarithmic 
> current-to-voltage converter. 
> 
> There are better ways to do this, but maybe none so cute. 

Or as risky.

-- 
Bill Sloman, Sydney

leads to this one...

https://www.dropbox.com/s/cgaxalnn3hhf315/RRIO_Logamp.jpg?raw=1

where we use the substrate diode of a RRIO opamp as a logarithmic
current-to-voltage converter.

There are better ways to do this, but maybe none so cute.




-- 

Father Brown's figure remained quite dark and still; 
but in that instant he had lost his head. His head was
always most valuable when he had lost it.